Multiarm hyperbranched polyester-b-Poly(ε-caprolactone):Plasticization effect and migration resistance for PVC

A series of multiarm structure hyperbranched polyester-b-poly( ε -caprolactone) (HEPCLs) with different lengths of poly( ε -caprolactone) (PCL) segments ( s = 3, 6, 7, 8) were synthesized. Hyperbranched polyester (HE) was synthesized from glycidol and succinic anhydride and used as a macromolecular polymerization initiator for ε -caprolactone. The HEPCLs were used as polyvinyl chloride (PVC) plasticizers and the mechanical properties, thermal properties, morphology, and migration stabilities of PVC films were explored. The plasticizing efficiency increased with the increase in PCL segments, and the plasticizing efficiency of HEPCL 8 exceeded that of dioctyl phthalate. Scanning electron microscopy and solid-state 1 H NMR showed that the HEPCLs possess better compatibility with PVC than HE. Moreover, HEPCLs exhibited excellent migration stability even at very harsh condition, indicating that HEPCLs can be used as no-migration PVC plasticizers in medical products, children's toys, and food packaging. J. VINYL ADDIT. TECHNOL., 26:35–42, 2020. © 2019 Society of Plastics Engineers